Rail and joint structure



July 9,1946;

H. L. LANSING 4 RAIL AND JOINT STRUCTURE 3 Sheets-Sheet 1 Filed Aug. 8,1942 13 LToraceL July 9, 1946.

H. LANSING ,403,807

RAIL AND JOINT STRUCTURE Filed Aug. 8, 1942 3 Sheets-Sheet 2 INVENTORvflbraceL.LaJ1Jsi239,

July 9, 1946. H. L. LANSING RAIL AND JOINT STRUCTURE Filed Aug. 8, 19423 Sheets-Sheet 5 INVENTOR liar-ace Patented July 9, i946 UNITED, ,STATERAIL AND JOINT STRUCTURE Horace L. Lansing,'Rutherford, N. J assignor toPoor & Company, New York, N. Y., a corporation of Delaware ApplicationAugust 8, 1942, Serial No.. 454,169

I 2 Claims.

. t t 1 This invention relates to improvements in splice bar forconnectingtogether the meeting end portions of railway rails, and toimproved railjoints embodying saidimproved splice'bars.

The object of the invention, generally speaking,is to provide asplicebar of novel construction for cooperation in a novel manner with therails which it isemployed to connect, whereby, in a joint embodying theimproved splice bar, a condition approaching the Optimum of advantaegeous stress distribution in both thesplice bar and the rail under bothbolting and wheel load forces imposed onthe joint; is attained with thematerial advantage emanating from such stress distribution. 1

With the foregoing general objectin View, the invention consists in asplice bar having the novel features of construction, and in a railjointembodying 'said bar having the novel features of combination andarrangement of parts, as will be hereinafter more fully described,illustrated in the accompanying drawings and defined in the appendedclaims.

In the accompanying drawings, wherein like characters of referencedenote corresponding 2 forms with said plane e an angle of not more than17.

The under faces of the bases of the splice bars may; be formed in anysuitable manner so that their contacts with the upper faces of the baseflanges of the rails are within the limits stated. Moreover, the saidcontacts, designated at 2:, may be surface contacts of any desiredwidths within the limits stated, or they may be line contacts, orsubstantially line contacts. Preferably, however, they are line contactsafiorded by convexly curving the under faces of the splice barstransversely as illustrated in the drawings so that as the bars aredrawn inwardly by the usual joint bolts I1, tendency of the bars to cockis minimized and proper seating of their bases upon the tops of the railflanges is assured. As to the heads of the bars, these may have flat topfaces or top faces of any other desired form engaging the or,alternatively and as is preferred, the upper inner'corners of the headsof the bars may be rounded and may have loading engagement with V thehead fillets l8 of, the rails as, shown in the four photo-elasticstudies. of rail joints. in which 1 t the splice bars have bearings uponthe base flanges 0f the rail' within and outside the limits of thepresent invention for saidbearings.

Referring to the drawings in detail, A, A designate the meeting endportions of a pair of railway rails, each including, as usual, a headIt, a web II and a base 12,-and B, Bdesignate a pair of splice barsconnecting said rails together and each including, as usual, a head IS,a web l4 and a base l5. 1

In accordance with the invention the vunder face of the base ofeach ofthe splice bars B is suitably formed to have loading engagementinitially with the upper faces of the related-flanges I6 of the railbases solely between a plane aincludin the central, vertical,longitudinal plane of the web of the bar and a plane b including theinner face of the web of the bar. Also in accordance with the inventionthe said initial loading engagement between the base of each splice barand the upper faces of the related flanges of the railbase isconfinedbetween a pair of downwardly and outwardly divergingwheeleload-line-defining planesc and at both of which intersect thecentral, vertical, longitudinal plane e of the rails at thetops of therails and the inner of which forms with said plane e an angle of notlessthan, 12 ,while the outer of which drawings. In any event-because ofthe initial loading cooperation of the bases of the splice bars with theflanges I5 of the rails within the limits stated, certain material andimportant advantages are attained. First, any tendency. of the bars tocook due to tightening of the joint bolt I! is minimized and properinitial seating of both the heads and the bases of the bars upon thehead portions of the rails and the railflanges l6,"respectively, isassured as aforesaidJsecond, I

the setting up of lateral bending stresses in the webs of the railsunder either bolt-tightening or wheel-load forces imposed on the jointare substantially entirely avoided; third, stresses in the heads, websand bases of the rails are minimized and dangerous stress concentrationsnear the upper and the lower apexes of the joint bars are substantiallyentirely avoided, particularly if the heads of the bars have loadingcooperation at their upper,.inner corners With the head fillets of the;rails as shown; fourth, tendency of the .rail flanges to droop underloads imposed on the joint are minimized; fifth, both bolting and wheelloads imposed on the joint are advantageously transmitted to the baseflanges of the rails at the points of minimum eccentricity of both therails and the joint bars, and, sixth, the bars are readilyself-adjusting to fit with the rails and to compensate for the inherentrolling variations in the bars and the rails.

Experiments have demonstrated that a, rail jointin which the bases ofthe splice bars have line contact or narrow-width surface contact withthe base flanges of the rails within limits as hereinbefore set forthafford an optimum of advantageous stress distribution in both the plicea u bars and the rails, and that shifting of said contacts eitherinwardly or outwardly beyond said limits results in progressivedeterioration of said advantageous stress distribution. This is clearlyevident from a consideration of Figs. 3 to 6 of the drawings which arereproductions of photographs of models of rail joints made from elasticmaterial and subjected in each instance to the same load correspondingto the bolting load imposed on the splice bars and the rails in actualpractice.

According to Fig. 3 the bases of the splice bars have loading engagementwith the rail flanges to- 1 ward the heels of the bars beyond the innerlimit of the present invention for said loading engagement. According toFig. 4 the said loadin engagement is approximately at the inner limit ofthe present invention for said loading engagement. According to Fig. 5the said loading engagement is approximately at the .outer limit of thepresent invention for said loading engagement. And according to Fig. 6the said loadin engagement is outwardly beyond the outer limit of thepresent invention for said loading engagement. The reactance member IS.at the right hand side of each of Figs. 3 to 6 shows by the number ofstress lines therein that the load corresponding to the bolting loadimposed on the joint by the screw 23 was the same in each instance;

Several trends will be observed from Figs. 3 to 6. First, it will beobserved that the regions of stress in the bases of the joint bars andthe base of the rail retreat inwardly as the base bearin'gs of the jointbars upon the rail flanges move toward the heels of the bars from theinner limit of the present invention for said base bearings. Second, itwill be observed that the amount of stressin the base of the railincreases as the base bearings of the joint bars upon the rail flangesmove outwardly beyond the outer limit of the present invention for saidbase bearings, due to resulting droop of the outer portions of the railbase flanges. Third, it will be observed that the amount of stressproduced in the webs of the joint bars also increases as the said basebearings moveoutwardly beyond the outer limit of the present inventionfor said base bearings. Fourth, it will be observed that the intensityof stress in the base-web connecting fillets of the rail also increasesas the said base bearings move outwardly beyond the outer limit of thepresent invention for said base bearings. Fifth, it will be observedthat the area of stress in the rail head decreases as the base bearingsof the splice bars upon the rail flanges move outwardly beyond the outerlimit of the present invention for said base bearings.

According to Fig. 3 the stress in the webs of the joint bars is aminimum, there is little stress due to droop of the base flanges of therail and no stress in the toe portions of the splice bars. However,there are high stress concentrations at all bearing points due to thetendency of the splice bars to rotate outwardly at their heads and thebearings located as indicated are impractical as the heels of the splicebars are very close to'riding the base fillets of the rail.

Fig. 4, as compared with Figs. 5 and 6, shows lesser amounts of stressin the Webs of the splice bars, lesser amounts of droop of thebaseflanges of the rail and no stress in the toe portions of.

the splice bars. Moreover, Fig. 4 demonstrates reduction in tendency, ascompared with Fig. 3, of the heads of the splice bars to rotate out- 4wardly and indicates practical take-up bearings of the bases ofjthesplice .bars. upon the rail flan es- I i;

Figure 5 shows the samecharacteristics as Fig.

- 4. A slight drooping of the rail base flanges may be observed togetherwith a spreading of the stress patterns in the bases of the splice bars,but

the condition is very similar to the condition shown in Fig. 4.

Figure 6 shows a marked increase in the stress in the webs of thesplicebars and an increased tendency of the base flanges of the rail to droop,with increase of stress in the base-web fillets of the rail as well asincrease in stress throughout the base of the rail. Figure 6 furthershows the strain pattern spreading throughout the-entire base portionsof the splice bars. I

In short, Figs. 3 to 6 of the drawings vividly indicate that a railjoint embodying splice bars having base bearings 'upon the railbase'flanges within the limits of th present invention afford a farsuperior joint as regards stress distribution than is afforded by adeparture of said base bearings in either direction beyond said limits.These figures of the drawings also exemplify the improved resultsobtained by reason of the position of the point of contact of the bar onthe upper flat fishing surface of the rail flange. That position is animportant part of the present invention as certain desirable advantagesare incident thereto. As herein noted the intensity of the stress in thebase-web fillets of the rail increases as the base contact of the barthereon moves outwardly beyond the outer limit of the present invention,and also the area of stress in the rail head decreases as such contactmoves outwardly beyond the outer limit of the present invention.

By reference to photo-elastic study of Fig. 3 the bearing contact at thefoot of the bar on the rail flange is well inside of the inner limit ofthe presentinvention resulting, as shown, in a heavy concentration ofstress or strain in both the rail and the joint bar in the zone ofcontact; and in the photo-elastic study shown in Fig. 4 the point ofcontact between the base of the bar and the rail flange is farther outfrom the base web-fillet than shown in Fig. 3, showing a decideddecrease in stress or strain within the base-web fillet, and also'in thebar. and inthe rail flange within the zone of contact. Thisrelativeposition of parts, as shown in Fig. 4, is within the scope of thepresentinvention, and likewise the position of parts shown in Fig. 5 ofthe drawings, which represents what might be said an outer limit, as faras the joint bar is concerned, also shows reduction in stress or strainin the baseweb fillet over that shown in the example of. Fig. 3 and alsoin the stress ,or strain concentration within the zone of contactbetween the bar and the rail flange. The illustration of'Fig. 6 whichdefinitely is outside of the limits of the present invention shows anextreme, but typical, advanced position, toward the outer edge of therail flange, of the point of contact between the splice bar and the railflange wherein the stress concentrations in the base-web fillet aremateriall increased, aswell as a manifest increased drooping of theedges of the rail flanges.

Consequently, it will be seen that in order to obtain the maximumadvantages of the use of the present invention with reference tominimizing of stress or strain in both the rail and the splice'bar, itwill have been noted from what is said herein and whatisshowntliedrawings;

that the point -of contact for the joint bar on the flat upper fishingface of the rail flange,- is preferably at a point on said surface ofthe rail flange between the outer edge of the base webfillet and thelongitudinal center of the said upper flat fishing surface of the railflange. Also, it is shown, as essential to the present invention, thatthe loading engagement of the initial-contact bearing element with therail flange is intersected by a plane at substantially right angles tothe upper face of the rail flange and lies between a pair of downwardlyand outwardly diverging planes, both intersecting the central verticallongitudinal plane of the rail atits top, at angles to said plane of therail of not less than 12 for the inner plane and not more than 17 forthe outer plane, thereby to confine the initial bearing element, and themajor portion of the area-contact developed therefrom by abrasion, onthe rail flange, between said diverging planes.

Prior to the development and utilization of the positioned curved basecontact in accordance with the present invention, there was considerabledifficulty in obtaining joint bars that had a reasonably good fit. Withthe advent of the higher rails the 112 and 131 R. E. due to increase infishing height, the variations in fishing and angularity of the fishingsurfaces became exaggerated- It was found that head contact barsdeveloped the tendency to cook inward at the head. The result was theoccurrence of a line bearing between the small upperouter fillet of thehead of the bar and the head of the rail with a concentration of stressalong this line and ultimately fatigue failures. With headfree barseither the initial contact occurred on the heel fillet, if the barsection was greater than the rail fishing, or at the outer edge of thetoe, if the bar fishing was smaller than the rail fishing- In eithercase the stress concentration was at a most disadvantageous location.According to the present invention it was found that all oftheseconditions were considerably improved by curving the base portionof the joint bar, and, in this connection, the location of the point ofcontact of this curve proved to be of vital importance. It was foundthat the position of contact advocated by the present invention gave theleast disadvantageous distribution of stress in both the joint bar andrail. Also, it was found that as wear occurred and the initial linecontact developed into an area contact of greater or lesser widthaccording to the amount of wear, the contact remained in the zone wherestress concentration isleast disadvantageous. It was additionallydetermined that, in order to insure against the development by wear of ashoulder on the rail flange, which might interfere with inwardadjustment of the base portion of the bar to compensate for wear, it wasnecessary that the curvature of the underface of the bar be such thatfrom its initial line contact with the upper face of the rail flange andfrom its subsequent area contact with the said upper face of the railflange developed by wear, it should constantly recede upwardly andoutwardly with reference to the upper face of the rail flange. In thisconnection the curved under face of the splice bar must extend inwardlyat least to, but neednot extend inwardly appreciably beyond, th pointwhere it contacts the upper face of the rail flange when the barinitially is applied, and, moreover, it must extend outwardly at leastas far as, but not necessarily 6 beyond, the outer limit of thewear-developed contact area between the bar and the rail flange when thebar has been adjusted to its innermost limit relative to the rail tocompensate for wear, Without further description it is thought that thefeatures and advantagesof the invention will be readily apparent tothose skilled in the art, and it will of course be understood thatchanges in the form, proportion and minor details of construction may beresorted to, without departing from the spirit of the invention andscope of the appended claims.

' I claim:

1. A rail joint structure comprising vignoles rails and a splice bar,including a head, a web and a base, having loading engagement at itshead with head portions of the rails and at the under side of its basewith. the upper faces of the base flanges of the rails, the under faceof the base of said bar being initially convexly curved transversely toa contour to have initial line .contact with the rail flanges betweenvertical f planes including the inner face and the center of the web ofthe bar, respectively, and between downwardly and outwardly divergingplanes which intersect the central vertical plane of the rails at thetops of the latter and which are disposed at angles to said centralvertical plane of the rails of not less than 12 and not more than 17,respectively, thereby to insure that initial and subsequentwear-developed contactbetween the base of the bar and the railflangesshall occur within limits transversely of the base of the bar and'therail flanges where stress concentration is least disadvantageous, thesaid under face of the base of said bar from its portion in contact withthe rail flanges constantly receding upwardly and outwardly withreference to the upper faces of said rail flanges to insure againstdevelopment by wear of any shoulders in the upper faces of the railflanges which might interfere with inward adjustment of the bottomportion of the bar relative to the rails.

2. A splice bar for connecting together the ends of vignolesv rails,said splice bar comprising a head to have loading engagement with headportions of the rails, a web, and a base having its under face initiallyconvexly curved transversely to a contour to have initial line contactwith the upper faces of the rail flanges between vertical planesincluding the inner face and the center of the web of the'bar,respectively, and between downwardly and outwardly diverging planes 7which intersect the central vertical plane of the rails at the tops ofth latter and which are disposed at angles to the central vertical planeof the rails of not less than 2 and not more than 17, respectively,thereby to insure that initial and subsequent wear-developed'contactbetween the base of the bar and the rail flanges shall occur Withinlimits transversely of the base of the bar and the rail flanges wherestress concentration is least disadvantageous, the said under face ofthe base of said bar being curved to recede constantly upwardly andoutwardly with reference to the upper faces of the rail flanges from theportion of said under face which contacts the rail flanges to insureagainst develop ment by wear of any shoulders in the upper faces of therail flanges which might interfere with inward adjustment of the bottomportion of the bar relative to the rails.

' HORACE L. LANSING.

